Minnows:?Big or small, tell me all/Biological Bits

March 29, 2013

When anglers hear the word minnow, they think of any small silvery fish. Some folks think of the SS Minnow on Gilligan's Island and perhaps it was named after the fish, but only Hollywood knows. They also believe there are very few kinds of minnows and frequently talk about blues, grays, pike and perch minnows as being the types of minnows. This is typically what they ask for when they purchase bait. Not exactly true!

Some also think that all minnows are the young of larger fishes and ask what they will be when they get older. Minnows, true minnows, are members of a specific family of fishes just as there are the trout family, the perch family or the muskie family. Fry and not minnow is the proper term for the newly hatched young of these families.

Minnow is a general term used to refer to small fresh and salt water fish, especially those used for bait. More specifically it refers to freshwater fish of the family Cyprinidae, the carp family. Yes, carp, including Asian carp, goldfish and koi are family members. This family is the largest of all fish families, with about 2,400 species worldwide. There are about 1,600 minnow species in North America.

Most of the minnow family members only live 3-4 years, a few 7-10 years, but some of the largest can live for over 20 years. They spawn in the spring or early summer and some species can have multiple broods. The smallest never get over 2 inches long. The largest minnow in North America is the Colorado pikeminnow, formerly named the squawfish. It can attain a length of 6 feet and weigh up to 100 pounds. Let's see you build a minnow trap to catch those puppies.

In Michigan 45 species of minnows are or were present. Most minnow species are more commonly found in the lower peninsula. Of the 45, four species have been introduced: common carp, goldfish, sucker mouth minnow and ghost shiner; three are extinct: weed shiner, ironcolor shiner and bigeye chub; and four are endangered: redside dace, silver shiner, pugnose minnow and southern redbelly dace. The Ontonagon River system has 22 species of minnows, of which only the common carp is not native to Michigan or North America, coming from Europe.

In addition to minnows, there are other small fish a local angler may likely encounter. The main one of these is the sculpin (family Cottidae), often called the muddler by fishermen and imitated by fly tyers. There are four species are present in our local waters. The slimy and mottled sculpin are the two residents of almost every area stream, which make great brook and brown trout bait. As a young area angler, a live sculpin always caught me the biggest brookies. The other two species, deepwater and spoonhead are found in Lake Superior and important as lake trout forage. Another important forage fish in area lakes and streams, are the darters. The darters, of which there are 15 species in Michigan , are in the perch family (Percidae). The three most common in the Copper Country area are Iowa darters, johnny darters and logperch.

Minnows are a very important part of the aquatic ecosystem in the underwater fish-eat-fish world, as expressed in the first verse of the song The Minnow & The Trout. Help me out, said the minnow to the trout. I was lost and found myself swimming in your mouth. Tip for the day: Baits that imitate them will catch more fish.

We have many native and non-native minnow species that are found far from their native range in our Michigan waters. How are they spread? Minnow dealers get their supply from harvesters who mainly seine them from various sources, Saginaw Bay being one. They then do not sort them, but sell them at what is called pit run to bait dealers, who pass them on the anglers. The well-meaning anglers then dump their left-over bait into the water thinking they will supplement the forage base. This action, although well-intentioned can impact the ecosystem of a given lake. One example would be Gratiot Lake, which was recently found to have a growing bullhead population. Bullhead are a species that have few predators and are not favored by anglers, thus their numbers grow rapidly and crowd out other forage and game fish. Therefore, a good rule of thumb would be not to dump your left over bait into the water, but put it on the shore where a mink or eagle may find a meal.